Premium
Reversible Acetonitrile‐Induced Inactivation/Activation of Thermolysin
Author(s) -
Ulijn Rein V.,
Janssen Anja E. M.,
Moore Barry D.,
Halling Peter J.,
Kelly Sharon M.,
Price Nicholas C.
Publication year - 2002
Publication title -
chembiochem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.05
H-Index - 126
eISSN - 1439-7633
pISSN - 1439-4227
DOI - 10.1002/1439-7633(20021104)3:11<1112::aid-cbic1112>3.0.co;2-7
Subject(s) - thermolysin , acetonitrile , chemistry , combinatorial chemistry , biophysics , biochemistry , organic chemistry , biology , enzyme , trypsin
Thermolysin is catalytically inactive in mixtures of 10–15 % acetonitrile in aqueous buffer. Unexpectedly, dilution of the inactive enzyme with acetonitrile leads to complete recovery of the catalytic activity in a similar way to dilution with aqueous buffer. Circular dichroism and fluorescence studies of thermolysin in the same solvent mixtures reveal discontinuous changes in the overall secondary and tertiary protein structure that correlate well with the reversible differences in catalytic activity. The spectra on either side of the minimum activity point are different from each other, a fact indicating that the enzyme may be able to access two active conformations which are thermodynamically stable in different solvent environments.